Hark; the time hath come for "Hey, Science,"
our intelligence-boosting feature in which we enlist real live scientific
experts to answer humanity's most interesting/ idiotic scientific
questions. Today: Is there an evolutionary or biological reason for preferring to have sex with people of a certain race?

The question, from reader M.: "Is some humans' sexual preference or sexual propensity for certain other
humans of a particular 'race' a biologically determined orientation or a
culturally constructed desire or a combination of both?" That is, can evolutionary biology tell us the reason why you're only "into" a certain race of person, for boning? Does the answer lie deep in your DNA? Or are you just a boring racist?

This is a much more complicated question
than it seems. The best I can do is to suggest a few things to think
about.

First, during the vast majority of human
evolutionary history our ancestors wouldn't have traveled far from their
birthplace and therefore would rarely have encountered individuals who looked
very different from themselves or other members of their group—i.e., people of
different "races." Thus, it's very unlikely that we evolved any
psychological (brain) adaptations, sexual or otherwise, that have to do with
"race." That's not to say, of course, that our ancestors didn't
detect and act on in-group/out-group differences, just that these weren't
"racial" differences.

Second, mate choice was an important
adaptive problem facing our ancestors, so we should expect natural selection to
have produced specialized psychological mechanisms designed to solve this
problem. Mate choice actually comprises many different problems, so we
should expect the evolution of many different mechanisms to solve them. Some
problems might be solved by mechanisms that requires little input from the
environment, and therefore develop in the same way in every environment.
E.g., what's the ideal amount of acne or other visible skin diseases in a
potential mate? Presumably zero. So a psychological mechanism that
follows the "rule": "prefer unblemished skin, all else equal," would have
been adaptive everywhere, and would develop in a relatively "innate" manner.
But what about, say, skin color? Ancestral human
populations lived in a wide variety of environments and consequently
evolved very different skin colors to cope with those environments. And
there was always some gene flow throughout the range humans lived in, which is
why we remained a single species. So one would not expect selection to
have favored an "innate" preference for any specific skin color.
What would have made adaptive sense is a mechanism that detects skin
color in the individuals one sees growing up and specifies a rule "prefer a
mate with the average skin color you've seen." And that seems to be more
or less what did evolve, with one caveat. Human female skin that is a bit
lighter than the local average was a reliable cue of nubility (women's skin in
the environments of evolutionary history tended to darken a bit with age and
successive pregnancies). All else equal, the best mate was a nubile
woman, so the most attractive female skin color in ancestral human environments
probably was a bit lighter than the local female average. Although it's
been some years since I read the scientific literature on this topic, the
evidence I'm aware of supports this prediction.

Obviously the environments of modern
industrialized societies differ in many important ways from those of our
ancestral past, so there are lots of evolutionary novelties to consider,
including: individual variation in physical appearance is far greater in
industrialized societies than it was under ancestral conditions; in
industrialized societies different people are exposed to different local
samples of their population; people are exposed almost from birth to media
images; and even mirrors, which provide a clear, stable image of oneself,
constitute an evolutionarily-novel input into our visual system that may affect
the development of the brain mechanisms that underpin our perceptions of
physical attractiveness.

These ideas are developed in much greater
(and probably more coherent) detail in my chapter, "Beauty is in the
adaptations of the beholder," in the book Sexual Nature/Sexual Culture, edited
by Paul Abramson and Steven Pinkerton, and in a little book by Catherine Salmon
and me, Warrior Lovers.

Pierre Van Den Bergh, professor emeritus of sociology at the University of Washington and author of many books on race, sexuality, and human evolution:

I believe the "natural" sexual preference is for partners who are
broadly similar to oneself, in good physical condition, and in control
of good resources, especially for women. Men tend to be more open to any
mating opportunity, and to be less choosy. Any narrow preference for a
particular type of sexual object, I tend to view as a form of culturally
conditioned fetishism brought about by prior experiences, whether it be
blond hair, red shoes or rubber gloves.

Brendan Zietsch, research fellow at the University of Queensland School of Psychology, studying human sexuality:

The
question is an interesting one. The short answer is: probably yes [it is determined by evolution] but
we don't know for sure. We do know that virtually all psychological
characteristics
that have been studies are to some extent heritable. In fact, my own
research shows that, compared with genetically nonidentical twins,
genetically identical twins have more similar sexual and romantic
partner preferences, which indicates that genes play a
role in those preferences. No one has looked specifically for genetic
influences on sexual preferences for different races, but I see no
reason why this would not be to some extent heritable as well. It is
important to note that 'to some extent heritable'
does not mean that these preferences are 'biologically determined',
only that genes play some role along with environmental influences which
could include upbringing and cultural prejudices.

The verdict: Though this is far from a settled question with a definitive answer, the consensus seems to be that evolution and genetics do likely play some role in humans' sexual preferences—quite possibly including racial preferences, although the exact nature of what goes into forming such preferences is unclear.

We can say definitively that there is not enough evidence for anyone to be able to say, "I only date [race] [women, men, or both] because that's in my genes." Open your minds, people. And your legs!

Previously

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